A short-circuit detecting device includes a coil and a processing circuit. The coil is configured to detect a variation of magnetic flux intensity generated by a current variation of a current flowing through a power semiconductor switch and to generate an induced electromotive force based on the variation of magnetic flux intensity. When the current variation rate of said current is greater than a predetermined value, the processing circuit is configured to generate a short-circuit signal based on the induced electromotive force so as to turn off the power semiconductor switch based on the short-circuit signal.